Device for signalling any change in the pull to which a yarn or the like is subjected



May 24, 1966 M. RATTl 3,253,269

DEVICE FOR SIGNALLING ANY CHANGE IN THE PULL TO WHICH A YARN OR THE LIKE IS SUBJECTED Filed Nov. 18. 1963 MAG/VET INVENTOR.

United States Patent 3,253,269 DEVICE FOR SIGNALLING ANY CHANGE IN THE PULL TO WHICH A YARN OR THE LIKE IS SUBJECTED I Michele Ratti, Via Monte Santo, Luino, Varese, Italy Filed Nov. 18, 1963, Ser. No. 324,470 Claims priority, application Italy, Sept. 5, 1963, 18,174/ 63 4 Claims. (Cl. 340-259) In spinning and twisting machines and the like, to assure a correct unwinding from and rewinding of the yarn on spindles, reels, cops and the like, it is necessary that the yarn itself, during such an operation, be subjected to a constant mechanical pull. A decrease in the pull may be caused by an irregular braking of the yarn passing through a succession of threadguides, during its running, or, in the case of a folded thread, by the breaking of the yarn.

The device according to the present invention allows to check during the operation that the pull to which the yarn is subjected, steadily be maintained at the established value and to adjust the pull at the beginning of the operation, whereby, if for any accidental cause said pull should diminish, the signalling members would intervene at once to signal by means of visual or acoustical means the operator, for his immediate attention.

The device according to the invention is characterized by two pulleys, or equivalent means, arranged along the path of the yarn, the first of which having its journal pin secured on the supporting frame, and the second pulley having its pivot secured on the end'of a counterweighed lever, in the way of a steelyard; to the pivot pin of said lever there being applied cams or equivalent means, which, inthe two extreme swing limiting positions of the lever, which are preferably made bistable, respectively open and close at least one alarm circuit, on said lever there being mounted two slidable weights, one of which serves for the initial calibration of the device, and the other one to establish the .pull value on the yarn, at which the alarm circuit has to intervene.

For a better understanding, the attached drawing represents a preferred non limiting form of embodiment ofthe device being the object of the invention.

FIGURE 1 is a perspective view of the device;

FIGURE 2 is a schematic front view of the device, in the operating position; and

FIGURE 3 is a schematic front view in the alarm position.

The device includes the two pulleys 1 and 2, arranged along the path of the yarn 3, moving in the direction shown by the arrows 4 and 5.

The pulley 1 is secured on the supporting frame 6 of the device, while the pulley 2 is secured on the end of the lever 7, pivoted in 8 and counterweighed in the way of a steelyard by the two slidable weights 9 and 10; the weight 9 serves for the initial calibration, while the weight 10 serves to determine the value, in grams, of the pull on the yarn at which the alarm circuit has to intervene, value that can be read on the scale 11 of the lever 7.

Fast to the pivot 8, about which swings the lever 7, there is applied the cam 12, which, in its alarm position, closes the contacts 13-14 forming part of the electric circuit including the lamp 15, fed from the source 16.

The lamp 15 is protected by a cover 17 (FIGURE 1), preferably made of a red, transparent material, for a luminous remote indication.

The same circuit may include also a bell, a buzzer, or other acoustical means for signaling.

A second cam, identical with the one in 12, is arranged coaxial and parallel to the first one, and is shown for convenience in the upper part of FIGURE 3 in dotted lines.

3,253,269 Patented May 24, 1966 This cam closes simultaneously with the contacts 13 and 14, two other contacts 17-18, so as to signal the alarm condition of the device to a general circuit, by means of a centralized lamp 19, or other means common to all the devices mounted on different machines, for instance all the machines in the room. Said lamp may be placed in a point easily visible in the room itself.

If the main lamp in the room is out, this means that all the devices are in their normal condition; if it lights up it means that one or more devices are not functioning properly and it will sufiice to inspect all of the machines to easily findwhere the trouble is. i Since the lamps of the single devices are generally aligned and arranged in an easily visible position, it will sufiice a glance to ascertain on which machine has occurred the failure.

The secondary small lever 20, pivoted in 21, with its lug 20 serves to keep moved to its lifted position, shown in FIGURE 1, the steelyardlike lever 7, when it is wished to take the device out of service. In the normal operation of the device the small lever 26 is pivoted to a position shown in FIGURE 2 where the lug 20' no longer keeps the lever 7 in its lifted position.

The operation is as follows: Be it assumed that the yarn 3 to be controlled (FIGURES 2 and 3), has to have a minimum pull of 8 grams. Then, the weight 10 is moved so as to correspond to the scale value 8 on the scale 11 (FIGURE 2). The whole is set so that as long as the pull T, urging upwardly the yarn 5 (FIGURE 2) is larger than or equal to 8 grams, the lever takes up a position such as to leave the contacts 13-14 and 17-18 open.

When instead the yarn pull falls suddenly below the set value of 8 grams, the lever 7 swings downwardly, that is from the inclined position shown in FIGURE 2 it moves to the horizontal position of FIGURE 3, thereby causing the contacts 13-14 and 17-18 to close and thus provide the optical (by means of the lamps 15, 19) or acoustical signal.

To help in such closing, the magnet 23 is attracted by the core 24, fast with the device frame, thus making bistable the posit-ion of the lever 7, in the sense that from its stable normal position, upon unbalancing, the lever is definitely brought to its second stable alarm position.

It is foreseen that the bistable device, instead of magnetically be made bistable through mechanical means for instance by a spring placed in a condition of unstable balance, as it has already been applied in certain types of electric breakers.

There is also foreseen the possibility of changing the shape of the different parts constituting the device, without departing from the field of protection of this patent.

What is claimed is:

1. A device for signalling the occurrence of a predetermined magnitude of tension acting on a yarn, the device comprising a supporting frame, a counterweighed lever having calibration marks, pivot means pivotally supporting said lever on said frame, said lever movable from an operating position to an alarm position, first and second yarn guide means for guiding the yarn, said first yarn guide means being mounted on said supporting frame in order to provide a constant path for the yarn, said second yarn guide means being connected adjacent one end of said counterweighed lever, weight means movably mounted on said lever to counterweight said lever and balance the tension acting on the yarn to normally hold said lever in said operating position, said lever being pivotal to said alarm position upon the occurrence of a predettermined magnitude of tension on the yarn, magnet means associated with said lever said frame for attracting said counterweighed lever to said frame when said lever is in said alarm position, said weight means being selectively movable on said lever to allow calibration of the predetermined magnitude of the tension acting on said yarn, and an alarm circuit operable in response to movement of said lever to said alarm position to indicate the occurrence of the predetermined magnitude of tension acting on the yarn.

2. The apparatus of claim 1 wherein a secondary lever means is mounted upon said supporting frame to be selectively pivoted into contact with said counterweighted lever to hold said lever in said operating position.

3. The apparatus of claim 2 wherein said alarm circuit comprises two cam means coaxially connected to said pivot of said counterweighed lever, each of said cam means being movable from a first position to a second position in accordance with movement of said lever :from said operating position to said alarm position, two pairs'of electric contact means having open and closed positions, one of said pairs of contact means being disposed adjacent each of said cam means, each of said cam means closing one pair of said electric contact means when said counterweighed lever is in said alarm position, two alarm means, each of said alarm means being activated by the closing of one of said electric contact means to indicate the occurrence of a predetermined magnitude of the tension acting on said yarn.

4. A device for signalling the occurrence of a predetermined magnitude of tension acting on a yarn, the device comprising a supporting frame, a counterweighed lever having calibration marks, pivot means pivotally supporting said lever on said frame, said lever movable from an inclined operating position to a horizontal alarm position, first and second pulley means for guiding the yarn, said first pulley means being pivotally mounted on said supporting frame in order to provide a constant position for the path of'the yarn, said second pulley means being pivotally connected to an end of said counterweighed lever, a pair of weight means being slidably mounted on said lever on opposite sides of said pivot to counterweigh said lever, the yarn passing under said second pulley so that tension acting on the yarn normally holds said lever in said inclined operating position, said lever beng pivoted by gravity to said horizontal alarm position upon the occurrence of a predetermined magnitude of tension on the yarn, said weight means being selectively slidable on said lever to allow calibration of the predetermined magnitude of the tension acting on said yarn, magnet means being attached to an end of said lever opposite from said second pulley means, said magnet means being attracted to said supporting frame when said counterweighed lever is in said alarm position, lever means being connected to said supporting frame, said lever means being selectively pivotal into contact with said counterweighed lever to hold said counterweighed lever in said inclined openating position, two cam means being ooaxi ally connected to said pivot of said counterweighed lever, each of said cam means having two operating positions dependent upon said positions of said counterweighed lever, two pairs of electric contact means having open and closed positions, one of said pairs of contact means being disposed adjacent each of said cam means, each of said cam means closing one pair of said electric contact means when said counterweighed lever is in said horizontal alarm position, two alarm means, each of said alarm means being activated by the closing of one of said electric contact means to indicate the occurrence of a predetermined magnitude of tension acting on said yarn.

References Cited by the Examiner UNITED STATES PATENTS 1,203,699 11/1916 Burke ZOO-61.18 X 1,635,478 7/1927 Hudson 200-61.18 2,074,237 3/1937 Pierce 200--61.18 X 2,281,188 4/194'2 White 5781 2,744,174 5/1956 Martin 200--61.18 2,824,184 2/1958 Mandeco 340259 X 3,044,052 7/1962 Marsh 340259 3,168,881 2/1965 Monin 20061.l8 X

FOREIGN PATENTS 788,906 10/1935 France.

NEIL C. READ, Primary Examiner.

R. M. GOLDMAN, Assistant Examiner. 

1. A DEVICE FOR SIGNALLING THE OCCURRENCE OF A PREDETERMINED MAGNITUDE OF TENSION ACTING ON A YARN, THE DEVICE COMPRISING A SUPPORTING FRAME, A COUNTERWEIGHT LEVER HAVING CALIBRATION MARKS, PIVOT MEAN PIVOTALLY SUPPORTING SAID LEVER ON SAID FRAME, SAID LEVER MOVABLE FROM AN OPERATING POSITION TO AN ALARM POSITION, FIRST AND SECOND YARN GUIDE MEANS FOR GUIDING THE YARN, SAID FIRST YARN GUIDE MEANS BEING MOUNTED ON SAID SUPPORTING FRAME IN ORDER TO PROVIDE A CONSTANT PATH FOR THE YARN, SAID SECOND YARN GUIDE MEANS BEING CONNECTED ADJACENT ONE END OF SAID COUNTERWEIGHED LEVER, WEIGHT MEANS MOVABLY MOUNTED ON SAID LEVER TO COUNTERWEIGHT SAID LEVER AND BALANCE THE TENSION ACTING ON THE YARN TO NORMALLY HOLD SAID LEVER IN SAID OPERATING POSITION, SAID LEVER BEING PIVOTAL TO SAID ALARM POSITION UPON THE OCCURRENCE OF A PREDETTERMINED MAGNITUDE OF TENSION ON THE YARN, MAGNET MEANS ASSOCIATED WITH SAID LEVER SAID FRAME FOR ATTRACTING SAID COUNTERWEIGHED LEVER TO SAID FRAME WHEN SAID LEVER IS IN SAID ALARM POSITION, SAID WEIGHT MEANS BEING SELECTIVELY MOVABLE ON SAID LEVER TO ALLOW CALIBRATION OF THE PREDETERMINED MAGNITUDE OF THE TENSION ACTING ON SAID YARN, AND AN ALARM CIRCUIT OPERABLE IN RESPONSE TO MOVEMENT OF SAID LEVER TO SAID ALARM POSITION TO INDICATE THE OCCURRENCE OF THE PREDETERMINED MAGNITUDE OF TENSION ACTING ON THE YARN. 